The SpaceX Polaris Dawn mission, led by fintech billionaire Jared Isaacman, launched early Tuesday from the Kennedy Space Center in Florida, journeying deeper into the cosmos than any humans in half a century, since the Apollo programme.

With the four-member crew’s Dragon spacecraft adjusted to an orbit with a high of 700km, pure oxygen began flowing into their suits this morning, marking the official start of their extravehicular activity (EVA) at 10.12am.

A short time later, Isaacman swung open the hatch and climbed through, gripping the hand and footholds of a structure known as “Skywalker”, as a breathtaking view of Earth unfolded below him.

“It’s gorgeous,” he told mission control in Hawthorne, California, where teams cheered on important checkpoints.

It was yet another major milestone for SpaceX, the company founded by Elon Musk in 2002.

Initially dismissed by the wider industry, it has since grown into a powerhouse that in 2020 beat aerospace giant Boeing in delivering a spaceship to provide rides for Nasa astronauts to the International Space Station.

“Today’s success represents a giant leap forward for the commercial space industry and Nasa’s long-term goal to build a vibrant US space economy,” Nasa chief Bill Nelson wrote on X, the social media platform also owned by Musk.